As they have been deferred through the extenuating circumstances system, the resits will be classed as your 1st attempt and marked uncapped. For this reason, you should do your utmost to attain a pass grade, even if it's in the 40% banding.
Should you not pass any of them, you will be given a 2nd attempt which will be capped at 40% anyway, but depending on your uni rules, you may have to repeat the modules concerned and you may not be able to progress to the next level. So, again, another reason to try and get through this year.
I think you need to take some urgent local advice from the SU and your Personal Tutor so that you fully understand what the regs are.
If you decide to go for it, we can help here with devising a revision stragegy.