Well that depends on many factors such as ship size(s) in a ship to ship transfer, cargo temperature, and return gas capabilities. The floating facility, such as used in Boston (take a look deeper in the Excelerate link I included) the cargo is vaporized (regased) aboard the feeder vessel and piped ashore into the land based pipe infrastructure.
In a ship to ship operation the feeder ship transfers liquid to the FSRU. Assuming the FSRU is cooled down you could expect 10,000 cubic meters per hour at full rate. The same goes for a ship transfer of LNG to a shoreside import terminal. The average turn around for the 1st generation ships, is about 20 hours which includes mooring, piping hook-ups, cooldown of the shoreside piping, rate up, rate down and custody transfer. Again a full rate at 10,000 cubic meters per hour is normal discharging through four 16" lines.
Keep in mind that an FSRU is pretty much like a peak shaving storage facility and regases at the rate of consumption ashore.
LNG ships are slotted in pretty much like aircraft. There is a pre-determined window for arrival and departure. A lot of logistics have to fall into place and all are subject to weather, especially the wind velocity and visibility.
I hope this helps. There are plenty of other links that can provide more information should you desire.
