The 319s can't even stick to the 323 schedule on the Man Airport to Piccadilly stoppers because of their poor acceleration.
In fairness to the 319s, Picc-Airport-Picc is a tight circuit, it's c.50 minutes scheduled running in every hour, plus two turnarounds, and I don't think the 323s would do substantially better.
Anyway, for those of you who think 319s aren't suited to Airports, here's a possible alternative duty I suggest they could have done.
Stockport CMD c.0540 ECS via Wilmslow to Manchester Airport for c.0620 (in order to exchange units with the 0640 Airport-Liverpool) then
c.0630 ECS Manchester Airport-Alderley Edge
0649 Alderley Edge-Picc
0738, 0938, 1138, 1338, 1538 Picc-Alderley & returns
1738 Picc-Crewe
1834 Crewe-Oxford Road
1943 Oxford Road-Wilmslow & 2056 return
2143 Oxford Road-Wilmslow
2225 ECS Wilmslow-Stockport CMD
There is additional mileage, Wilmslow-Airport-Wilmslow, compared to the present routine, but I suggest it's justified if it's going to eliminate the need for the pantomime which currently takes place at the Airport at c.1840 most evenings.
The 0630 Stoke-Picc, arr Picc 0727 (covered by a 323 ex Longsight) would need to do a quick turnaround to do 0732 Picc-Macclesfield.
It's too late now, of course, if it's all going into the melting pot in May.