Both the P.86 Stock and the P.89 Stock were sold to EVAG in Essen, Germany. They are at work on the Stadtbahn lines U11, U17 and U18.
Amazingly, the P.86s can now work in multiple, which they did not do in London. The P.86s went into service in Essen in their DLR colours and seating moquette. Only now are they being converted to have sliding doors in place of the folding 'batwing' doors and repainted in yellow with grey around the side car windows. Of course, they were fitted with cabs and pantographs before working on the Essen system.
The P.89s already had single leaf sliding doors before they left the DLR, having been converted at BREL. This was done because at the time it was thought they would be staying on the DLR and converted for the new signalling system. However, in addition to cabs and pantographs being fitted in Essen, they were repainted in yellow and blue and had new seating moquette.
Now, to answer your questions.
The last P.86s ran on 07.07.95 and four vehicles (01, 04, 07 and 09) ran on this day. However, the first departure to Essen was vehicle 11 on 14.11.91, this being that used for the trials in Manchester before the DLR opened, and the vehicle used for the DLR Royal opening in July 1987. The last vehicle to depart the DLR for Essen was 04 on 15.12.95. The first P.86s in service in Essen were 06 and 11 in November 1994. 01-11 were renumbered 5201-5211 before running in Essen.
The last P.89s ran on 07.07.95. All were officially available for service that day, although I am unsure if all were in service or not. 12-21 were renumbered 5221-5230 in Essen. The first two vehicles (14 and 21) left the DLR on 12.12.96 and the first to enter service in Essen was 15 (as 5224) in December 1999.
The refurbished P.86s are being renumbered on refurbishment in the 523x series, so if they follow on from the P.89s, they will be 5231-5241 (subject to checking and confirmation).
As far as I know the P.86s were not designed to run in multiple. When they were ordered, the 11 single vehicles were all that were expected for the DLR initial railway. But that soon changed .....
The P.89s were designed for two-vehicle operation.
The P.89s were converted to single leaf sliding doors in 1991-92. The first unit to be done comprised the damaged ends of 15B and 18A. Vehicles 15 and 18 collided previously at West India Quay Delta Junction and was the first train sent away, not only for door conversion but body repair as well. The unit was renumbered 15. The undamaged 15A and 18B was renumbered 18 for service and went away for door mods in May 1992.
The last (door) converted unit back was 21 on 12.08.92 and went into service on 31.08.92 (along with repaired and converted 15B/18A which had become 15.
P.89s did run to Bank both with their 'batwing' doors and with the later sliding doors.
First P.89 was delivered was 12 on 12.12.89, last was 21 on 04.05.90.
First in service was 12 on 11.05.90 and the last was was 21 on 22.02.91.
I also have in my notes that, although P.86s were banned to Bank in passenger service (not built for tunnel running), one did operate on 11.07.90. 03 was hauled by a diesel loco on test and was the first train to reach Bank!
On 25.02.91 the first two-vehicle DLR train operated, comprising 12+13 in the midday off-peak.