What is the earliest cut-off time you can set for Prime orders for SFP? Is it only 2pm?

Hello, so I have a handling time of 1 day for one of my ASINs (custom product) with the cut-off time at 11:30am. Ive also made sure to set the correct shipping service for that cut-off time and even if the order comes in at 10pm at night im still required to ship by the next day. I assumed that by setting the cut-off time the order, any orders that come in after that will add an additional day to the handling time. Am I doing something wrong here?

I know I can technically set the handling time to 2 days but even then if the order comes in late at night I have less time to fulfill the order. I dont want to add too many days to the handling time as that is not ideal.

Seller Central Top Right Corner: Shipping Settings -> *New* Location Tab -> Pick a warehouse -> Edit

Next Page, Order fulfillment settings -> Edit Shipping -> there we can setup cut-off time for FBM shipping options

1) Is the cut-off time refer to local warehouse time or GMT time?

2) Previously when this new feature was not available, we set the most east coast warehouse time zone and the earliest cut-off time was 2PM (EST). Now the new "location" setting allow us to setup such cut-off time as early as 1AM. If I set up the cut-off time at 1AM (EST), Is it kinda like the system give me 1 more day lead time to prepare orders?

Can someone help answer these 2 questions? Thanks.