The new gym update changes how coins are earned, including a limit of 50 coins earned per day. How does this limit work? Is each pokemon limited to accruing 50 coins per day? Are all my pokemon limited to a collective 50 per day? My teammates keep feeding my Dragonite and she has been at the gym for almost a week; will she return with 50 coins for each day she was there? Fewer than 50 for the days I had other pokemon in the gym? Or will she accumulate vast sums of coins over the week, but only deliver me 50 (or fewer) when she comes back based on what I have collected from returning pokemon that day?
You are limited to a total of 50 coins a day. That means your Pokémon are also limited to 50 coins total (since you can never get more than 50 in a single day). This means that once your Pokémon has been in a gym for 8 hours and 20 minutes (500 minutes), they are no longer accruing any coins for you.
For example, if you have 10 Pokémon in gyms for a week each, but they are all returned to you within the same day, you will only receive 50 coins. If they are kicked out one per day, then you will receive 500 coins total, 50 per Pokémon for 10 days.