“A Quick Salvage Run” 2nd ep of s2 takes place either concurrently or after TLJ so the Colussus arrives at the now destroyed resistance base from the end of TFA and beginning of TLJ. They have no fuel for another jump but there’s a big juicy First Order Dreadnought wreck to pillage (Thanks Rose’s Sister) 

The Star Destroyer is either taking low yield potshots at the station (I guess hoping to disable) or Colossus got some good shields all of a sudden