Please help! early morning shennanigans

please help! i have 2 6 months old kittens (brother and sister) who were as good as gold up until about a month ago-now at intervals throughout the night (sometimes as early as 2:30) she starts headbutting my bedroom door and scratching and mewing (crying) for about 3 minutes at a time before going away and coming back an hour or so later to do it again. Unfortunately they are restless when allowed to sleep in the bedroom and roam all over the bed and our house is relatively open plan so i don't have anywhere to shut them in.

any advice would be very much appreciated as my door is in pieces and i'm at the end of my tether

thanks in advance

First of all, are they both neutered?

After that, all I really have to offer is the usual, "Tire them out before going to bed."

But probably the real solution is about 6 more months of life for each of them. Six months seems to be the age at which they get this way.