You will be in on the edge of an RTK fix.
Maximum Baseline fo RTK for an L1 system like the RS+ is 10 km. If you would do it with PPK, it probably wouldn’t be much of an issue, excellent skyview granted.
The RS2 would be much better, as here the maximum baseline is 60 km.
For a relative accuracy test, I did this test with the RS2: Reach RS2 placing avg 1.6 cm RMS GCP with a 130 km Baseline - #2 by richie1aubyn
It’s awesome, and has the mobile data connection built in, which is much more convenient and reliable than using the phone hotspot.