Warped plates over columns during glaze firing

[Cumulus.mx]

Hello! I am creating small plates for a cafeteria and during the last of the glaze firings I wanted to be able to fit all of them in the same firing (they were only 2 left and didn't want to have to fire an almost emply kiln), so I used some of my columns as props to create different heights and intercalate the plates to fit them all in one. Ingenious me thought it would work. When I opened the kiln, the plates which were on top of the columns have slightly bent downwards. Does anyone know if I fire them again, this time flat, will they flatten again? Thanks!

[neilestrick]

They may fire flat, depending on the type of clay you used, but they may  not. The glaze may also come out different, but it may not. At this point you've got nothing to lose, so it's worth a try. In general, unless you're firing to low fire temps, you should always have the pieces sitting flat on a shelf.

[Rae Reich]

My first rookie mistake in kiln loading! My plates were larger and drooped irreparably, some onto the rims of other peoples’ pots.  The lab tech watched me do it and left me to learn the hard way. 
I can laugh now 

[Cumulus.mx]

Thank you @Rae Reich and @neilestrick for your responses! 
I did fire them again, some of them did flatten again and others didn't flatten enough. Lesson learnt! 

[Babs]

I too have used shelf props but topped them with bits of broken shelf size of base of pot