I believe, PAK is going to play Ahmed & drop Haris. The reason being, the way the squad is picked, I see an effort to bring back Ahmed. Normally, if a seasoned player is dropped (he is in his 9th year in PAK cap now), what every other team does is that they select the next man in contention and pick a rooky as back-up. That senior guy (who is dropped),has to go to domestics, perform and wait for his time for first the incumbent fails, then the rooky as well. A classic example was Hayden - After Mark, Slater they did get the chance, failed, so Aussies tried Elliot - finally Hayden came back after almost 4/5 years later and this time stayed.
Here, PAK dropped Ahmed for his failure against all conquering Lanka attack and his back-up (Amin) is picked, but instead of picking a rooky (Mukhtar, Farhan, comes to mind) Ul Haq has gone back to Ahmed the very next tour - now if Amin (or FZ) fails in 1st 2 games, Ahmed'll be picked and almost certainly he'll be retained in next series ...... then we go to the same cycle again for 2 years. This started from Ul Haq (Captain) era, mastered in Misbah era and now Ul Haq is taking it to next level as CS - hence by 2020, won't be surprised if PAK's T20 squad reaches an average age of 35 (38).
1. FZ
2. Ahmed
3. Babar
4. MoHa
5. Amin
6. Sarfraz
7. Shadab
8. Fahim
9. Nawaz
10. Hasan
11. Amir
This is probably going to be the starting XI for 1st game (or may be Hari comes for Ahmed & Amin opens - Hari won't happened had Mian been fit) ....... I am sure, had there been a Test series followed by T20, Ul Haq would have picked almost same squad - this is called revolution.