LJJ
Congratulations on your award and thank you for your comments.
You can request both the ESA85A and LT54 without risk to your current award, one or both of these should indicate the basis of your award.
I think you may be reading too much into the change from Incapacity Benefit to Employment and Support Allowance
Both IB and ESA are awarded to those, who due to disability or illness are unable to work.
Whether you wish to continue to receive ESA is entirely up to you, but I would strongly recommend you get face to face advice before making a decision on this, so that you can understand fully the financial implications of such a decision.
Gordon