Appears 7/18/18 Earnings call didn't reveal new deliveries. Some notes:

Industry leading on-time performance
10.4% margin, all areas up except Latin America, which has political/economic issues and travel warnings. Atlantic the best JV working great - Pacific first positive quarter since 2014
Basic Economy added to Latin America and Europe.
Minor capacity growth reduction due to higher fuel prices
If the economy dips, UA has flexibility to remove aircraft from service with big maint checks coming and lease returns
Stated UA took possession of first HA 763 yesterday. N588HA still shows in MCI and N684UA shows no movement
Still looking for used aircraft.
Flight Attendant groups will be merged by the next earning call.
Still searching for CFO with airline experience
25 new E175s will have 70 seats as they replace CRJ700 under scope clauses. Economics do not allow RJs to operate with mainline crews. Instead, UA is up-gauging to mainline. UA open to new leet types, inclduing small narrowbodies, but every new fleet type adds expense to manage/train.
Rebanked ORD and IAH hubs showing more connections and PRASM growth.
Fuel is going up, otherwise cost kept well in line.
Polaris is on track with new unit expected every 10 days through 2020.

My math would show about 91 units would be converted or introduced as new with that formula. I count 149 total WB aircraft possible to get Polaris: 5 remaining 3 class 763s, 21 2 class 763s, 3 HA 763s, 16 764s,31 remaining sUA 772ERs, 22 sCO 772s, 12 788s, 29 789s and10 78J. Maybe some fleets will take more time than 12/20 to convert. Or, can we expect the 21 763s, 16 764s, 12 788s may not get Polaris? That would equal 102 units. Dropping 25 789s would be only 77 Polaris units.