Vertical line at fix distance with specific ticktext

I have this graph to plot

The xaxis value of the date represented by the Ref vertical line can be anything .but It should be always plotted near to y axis at some distance with respective date.All the other trace are plotted as usual.

The problem here is all the other traces are respecting xaxis scale except Ref trace .(see blue arrowed date,it is placed disrespecting the scale).So I need a solution in which i can disrespect xaxis scale partially ,here for Ref trace.
I thought of multiple solution ,but nothing is helping me out in this situation.

Any help would be appreciated
Thanks

Can you share a code snippet of what you’ve tried so far to help us help you?