Apple Watch Series 3 - not enough space for last 2 updates

Hi. I've had this issue twice now following the 2 most recent Apple Watch OS updates for 7.0 and now 7.2. When attempting to install the update from my iPhone or directly on the watch, I'm told there is not enough storage space. I can't remember the specifics for 7.0 and in the end unpaired my watch and set it up from scratch which did in turn allow me to update to 7.0.

However trying again to get 7.2 I'm facing the same issue. Not enough storage. According to the watch app on my iPhone, the update size is around 400MB. I get that it may be compressed and needs more storage space to actually complete the install. I have 2.1GB of storage free, yet the update requires 2.7GB. I've followed the steps found here If you don’t have enough space to update your Apple Watch – Apple Support, and am again unpairing my watch and setting it up from scratch.

I find it hard to believe that I will need to go through this every time there is an update for a supported watch. Has anyone else found a way to get this to work without unpairing?

FYI, i do not have any additional apps installed on my watch, nor music or photos. Used primarily for notifications and activity app. Thanks.