I have now education plan and my four boards were done with a free plan, i don't know how to move them

so i did four big boards with a free plan (which  cannot remake from zero, it took 2 weeks).
i asked for education plan in the meanwhile, but by using the mail of my university and not the free plan gmail account. now i do not know how to have my boards in the education plan with university mail !
i asked for education plan just to have the possibility to download the boards as good quality pdf but it says i cant when i share them , because the account they are made with is still a free plan so i cannot download them neither from the paid education plan . 
im desperate and dont know what to do