Soupy
You are doing brilliantly and with the increased time you'll have from going back to part time plus the lengthening days and (hopefully) improving weather you will easily manage to fit in all the plan and everyone says that the plan does work and will get you round.............
People like you and me are not likely to be challenging the podium positions but the way I look at it is (or try to in my more positive moments!):
"the harder the journey the more worthwhile the reward"........
I know my journey will be very hard:
- full time job
- 3 dogs
- middle aged
- 1st ironman
- overweight
and dog only knows what else!
But as you say I know how much I would regret not trying...........all too often in my life I've wimped out of things - mainly for stupid reasons - some big things some little things - but I have never failed to regret each one..........
Now I know for a fact that at least 3 of my "negatives" don't apply to you and I also know that your cycling has come on leaps and bounds (by your own admission and Dustboy's appraisal), you've been enjoying your swim technique stuff, you are an experienced runner and you have the chance to train with other pie-rights who will give you all the advice and support you could possibly want.........
..........so in summary
YOU WILL DO GREAT GIRL! 
And so endeth the sermon for today 