After testing the methodology in the workshop, I finally bit the bullet today and replaced a UBNT sector with an ePmP2000 and elevated 17 clients. I had previously moved a couple of XM devices to other sectors, to try to mitigate against possible problems with them.
The process was reasonably straightforward, witha couple of banana skins almost tripping me up!.
I did it at tower site rather than from office (in case a truck roll was needed).
Rather than load the firmware via Aircontrol I did each SM one at a time (or should that be CPE at that point.!), streamlining the process slightly by putting the file on my Macbook desktop, as each time I browsed for the elevate F/W, as each time it is a new connection, it started me at the desktop rather than the nested folder where I normally store such files.
Then the rigger quickly swapped the sector over on the tower - unfortunately there was no room to have both UBNT and ePmP2000 on the tower at the same time.
Held breath and waited for the SM's to associate, 1....2,,3,,4....pause, 5...pause, 6, ,7, 8, 9, 10, 11, 12...11, and then no more.
Waited a few minutes, twaeked the elevation and azimuth, still no more!
Went through the 11 SM's that were back, and ticked the frequency list boxes, so that they come back more quickly after changing anything, and noticed that although they had figured out that the UBNT CPE's were set up as routers, and had come back as NAT (which is correct) they hadn't 'realised' that DHCP was switched on, and although they had filled in the DHCP start and end ranges and were in the correct subnet, they were not starting and ending from the same address (100 - 120 in our case), so consequently the client wasn't online until I corrected this with each SM.
After this, there was still no sign of the missing 6 SM's, so I was bracing for a 'truck roll'.
Before resigning myself to that, I ldecided to look at the map view of the now offline ex UBNT CPE's to see if there was any common factor btween the missing SM's - and there was! - They were all four or more miles from the AP, while the connected SM's were less than 3 miles.
Another look at the AP settings, and I spotted the 'Max Range' setting in 'Access Point Configuration' was set to 3 miles!
Changing this to 6 miles and the missing SM's all associated!
So it's a learning curve!
It would be useful if some sort of UBNT to ePmP 'culture difference' guide could be complied to aid the unwary!
Looking at the performance, all looks good, with the AP happlly supporting 60Mb of traffic, a threefold increase over the UBNT sector!