The original 1983 miniseries was clearly set in the 1980s (as depicted by the fashions and music that is heard), but this series now has those events taking place in the 1970s.
The 1983 miniseries established that Sarah was Stephanie's elder child and Dennis the younger one (she was born from Stephanie's first marriage and he from her second). However, this has now flipped: Sarah refers to Dennis as her "big brother" in their first scene together.
It is stated that Jilly has spent seven years in prison, partly for her part in the attempted murder of Stephanie and partly for the manslaughter of Greg Marsden--both in the original 1983 miniseries. However, Jilly didn't actually try to help Greg kill Stephanie (though she did withhold the truth from the police), and she didn't actually kill Greg. She shot him in the arm when he tried to murder Stephanie a second time, but he survived this and escaped in a small plane, crashing it a few moments after take-off.
Keith Aberdein was credited as one of the series' associate producers and was given a recurring role as Johnno Ryan. As if that wasn't already a stretch, the character managed (quite inexplicably) to bed both Jilly Stewart Peta Toppano and Stephanie Harper Rebecca Gilling, which stretching credibility beyond all limits.