That cushion cover kit sounds really poor quality, what a disappointment! Definitely avoid that supplier in future. I hope you manage to complete the kit with what you've got.

Well done with the weeding, but definitely don't overdo the bending or do anything too strenuous. Surgery recovery can take quite a while.

That's... a huge time commitment, good luck with the training courses. Timetabling does sound like a good idea. You can always do an extra session now and then on top of the ones you've scheduled time for, if you feel like it. The six hour long modules sound tough though.