4L80E - Delay in Reverse Engagement

Recently had the 4L80E (220k miles) in my 96 K2500 4x4 Pickup rebuilt by a recommended local Transmission Shop. Since getting the truck back, when shifting into reverse, there is a delay before engagement of approx 2-3 seconds. Took the truck back to them to be test-driven and they say it's a normal thing. The thing is, I don't recall the truck doing that in the previous 120k miles I drove it.

2-3 seconds is a long lag, especially when the thing is warm.

Any ideas on what the shop could have done to cause the issue?

Just to make sure - you’ve checked the fluid levels?

Yes, have checked the trans fluid and it's where it should be.