You’ll probably be able to read your Kindle as your plane climbs into the sky on the way to Grandma’s house for the holidays, but if you bought a discount plane fare and refused to pay extra for early boarding, you might have trouble finding space for your roller bag.

Like bags in an overhead bin, flying conditions tend to shift, and there are some new wrinkles as this year’s holiday travel season approaches.

One good piece of news is the Federal Aviation Administration’s relaxing of rules on the use of portable electronic devices on airplanes. The way the airlines are trumpeting the change, you’d think travelers were about to get food or something. But the change is simple: Previously, you were able to use electronic readers such as Kindles, along with tablets and phones in airplane mode (using onboard Wi-Fi if available), only above 10,000 feet.

Now, you can do exactly the same thing below 10,000 feet. You gain 10 to 20 minutes of extra time for reading, game-playing and emailing. You still can’t make phone calls or send texts. But at least you’ll be able to keep reading while the plane ascends and descends (assuming you can hang onto your device while the aircraft flops around on takeoff), and Alec Baldwin won’t be tossed for playing Words With Friends after the cabin door is closed.

JetBlue and Delta were the first airlines to relax their electronics rules, with American and United close behind. FAA spokesman Lynn Lunsford says he expects every major airline to offer the relaxed device use by the end of the year.

The second positive change is that more travelers than ever are enrolled in TSA’s Pre-check program, which lets you keep your shoes and belt on, keep your laptop in your bag and go through security in a special line. TSA says nearly 18 million travelers “have experienced” Pre-check, although not all of those are enrolled. (Recently, TSA has begun occasionally pulling unenrolled people to send through the Pre-check line; that’s how you can “experience” it without being enrolled.)

So many people are experiencing Pre-check, in fact, that travelers are beginning to complain that some Pre-check lines, especially in big airports such as Washington-Dulles and Newark, N.J., are as long as the regular lines.

And that’s before Pre-check lets the huddled masses into the program, as it is planning to do any day now. Right now, Pre-check is primarily for people considered elite passengers by certain large airlines. It’s not a matter of how often you fly; it’s a matter of how much you spend. You can also get into the Pre-check line by being a member of Global Entry, which also gets you into a speedy passport-check line when you return from traveling abroad. Global Entry application costs $100 and involves passing a security clearance and personal interview.

TSA is planning to enact a procedure very much like Global Entry’s for enrolling in Pre-check, except that the Pre-check fee is expected to be $85. An in-person interview will be required. Because of the interview, don’t expect to get into Pre-check by the holidays. That said, at any moment, TSA could announced a little gift in the form of your ability to sign up for it without being one of your airline’s elite travelers. (For those of us who travel internationally, Global Entry is probably worth the extra $15, since the processes will be nearly identical.)

Now for the bad news: Airlines are providing more and more chances for you to pay extra to get on the plane early. Getting on the plane early, as you know, equates to getting bin space for your carry-on. When you book your ticket, you get a chance to pay extra for priority boarding on most airlines. Some even often a second chance at the gate. One Southwest flight recently was trying to sell some of its first 30 positions for $40 each as the flight began to board.

It’s gotten to the point that on many flights, more than half the passengers are in some sort of priority-boarding group. Some airlines — United, for example — flat-out tell you on certain flights that if you’re in the last boarding group, you have no hope of getting any bin space.

So, what are you to do if you don’t want to pay extra? First, if you have a credit card affiliated with an airline, sometimes paying for your ticket with that card will get you priority boarding. Second: If you’re carrying on a roller bag, also take a carry-on that can fit under the seat for your wallet, keys, valuables, prescriptions and electronics. Your wheelie bag, then, should contain only clothing. If flight attendants have to gate-check the bag, your important stuff stays with you.

Also, as we told you at the start of last summer’s travel season, leg room and seat width are both getting tighter on many airplanes so that airlines can squeeze on more seats. Some airlines say that the new seats are thinner, so you won’t notice much change, but some travelers disagree.

After you’ve heard all this, do you still want to fly somewhere for the holidays? Here’s one other good bit of news: A quick check shows there are a good many seats left on airplanes for Christmas week, and they’re not exorbitantly priced if you buy them 21 days in advance. For flights departing Dec. 23 and returning Dec. 28, fares were as low as $370 to New York-LaGuardia and $380 to Orlando. That’s flying on a Monday and Saturday. You’ll typically pay more to fly on a Sunday.

Last, if you’re flying out of Austin-Bergstrom International Airport, be aware that there’s a lot of construction going on — some to expand the terminal, some to consolidate car rental operations, some to enlarge Parking Lot G. None of that should impede your progress. Workers are always there pointing the way to available parking. But things look a little different, and barriers will funnel you in new directions.

Do remember that during holiday periods, lots can fill up. It’s better to have someone drop you at the airport. Also, during holiday periods, especially on any day children are out of school, you should arrive two hours early for your flight, because extra people will be taking wing, phones and tablets in hand.

Photo Credit: Southwest doesn't yet allow gate to gate use of portable electronic devices, but once the aircraft gets to 10,000 feet, then passengers can get access to free DISH TV programming during their holiday travels. Southwest