Wireless Joint

Using EM20-G I currently hit one tower 3.6 miles away.
There is a tower in town 1.6miles away that I'm thinking about switching to to get B66 for DL.
Every now and then this tower in town has a 6 to 7 hr window that it get really slow like 1.0mbps DL speed, seems to happen to my brother who is using that tower about once every few months so i know it happens.
here is my question i want to hit the in town tower (1.6miles) with my main-aux antenna and hit the other tower that is 3.6 miles away with my M1-M2 antenna.
here are the bands on each tower
Town Tower 1.6miles- Band- 2, 4, 12, 30 ,66
Other tower 3.6 miles- Band 2, 5 12 ,30

antenna information
Main-is Parabolic Dish Operating Frequencies: 600-6500 MHz
Aux - 700-2700MHz 15dBi <--panel antenna from The Wireless Haven
M1- 700-2700MHz 15dBi <--panel antenna from The Wireless Haven (i know the floor is 1700 on M1, M2)
M2- 700-2700MHz 15dBi <--panel antenna from The Wireless Haven

I'm trying to save myself some trips on the roof so any input is welcome.

Thx

It would be helpful to also list the carrier you're using.
Anyway, try locking the modem to each of those bands one at a time, run some speeds tests, then go from there.
By the way, nowadays with this pandemic most everyone staying home, all the mobile networks are more congested than normal, therefore slower speeds are to be expected.

AT$T is the carrier ,, im still at 90% pre-pandemic numbers on downloads its a rural area,
weather is cooperating today so ill finally get them on the tower.

I tried this and it did not really work that well, i do not recommend this course of action.