It isn't our place to judge the OP. She has decided on behalf of her horse (which we must accept she knows better than any of us) that towards the end of the year he will go. This decision has evidently not been made lightly and we shouldn't sow seeds of doubt or disagree with her reasoning.
I'm not going to say what I think in this instance; I will agree that a plan is definitely a good idea but should also have contingencies for the unexpected.
How and where and when is up to her, and again is not up for debate.
gable is the only one who has to live with any regrets - and they could be that she didn't do it sooner as well as left it too late. I hope it all goes well and exactly to plan.
Sadly, I think the insurance won't cover pts costs. I am a chicken and couldn't tell you how much the injection cost me - I said fill in the cheque because I don't want to know

She lies in my top field.