Out of curiosity as to why do many medronic users seem to have this issue ( including one of my close friends ) I did some googling and found this.
So you can't manually set the TDD like you can on tslim and its based on the last 6 days needs, so for arguments sake, if you average about 25 units a day and suddenly need a massive correction ( like say 5 units ) it isn't going to let you have that much as it won't go over the 25 limit. The only way I can see around this would to be to give a few ' ghost ' units at the end of each day, that would give you a higher TDD and more insulin available for correcting.
Closed loop is fabulous but none of them are perfect yet but I'm sure over time tweaks will improve them.
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