DEG, the instructions I was given for Sandrena was to rub on outer thigh. I had to use 2 x 1mg sachets, so did one on inner thigh and one on outer, alternating sides each day. Sounds as though you will have to find some sort of compromise if you cannot ring the changes, I doubt it will matter too much.
I was switched to Sandrena because of absorption problems with Oestrogel. My serum estradiol level did go up a bit but not enough, so I am now on Estradot patches. Only started them this month and not due another blood test until April, so it remains to be seen whether these will work.
Best wishes, JP x