Since I been done this in all my modems 4G and 5G before, there is very few routers who offer the possibility to hook an antenna to improve the signal. I am seeing the sim cards in the router are under the battery (not great).
Would be seeing a possibility of access the modem without breaking the body of this device?
I am also living this post here to leave a future mod if I receive the router.
This is how I did it with my Beryl AX. I removed the original antenna’s and put a SMA connector in place so I can use external antenna’s on my boat to catch harbor wifi. On the photo’s The antenna’s are removable. I have added rail mount to as it Will be put inside a panel
I expect this can be done in the same way. Open the device, check your antenne connections and remove the antenna. The move the connection to outside in the housing and connect a suitable 4G or 5G external antenna.