Benzodiazepine substitution

[Rob2020]

Hello , I posted a similar question somewhere before but I think i put it in the wrong place and possibly worded it incorrectly. Anyway, I’m having another go here and maybe someone can give a view.

i have used Lorazepam regularly for a number of years.  I don’t use it in high doses or more than once a day and I don’t abuse it.  However, I do have some dependency on it and , if I miss more than one day I start to get rather unpleasant withdrawals.  I do intent to get to this resolved with my GP - but not immediately. Anyway, I’ve screwed up on my refills and I am running very low indeed.  I can’t get an appointment with my normal doctor for at least a week and, to be honest, given the current situation, they’re so stretched I don’t even want to bother them.  
However, although I’m almost out of lorazepam, I do have access to some equivalent strength Xanax.  It’s clearly not ideal but if I used the Xanax as a temporary substitute for the Lorazepam, is it likely to stave off withdrawal ?  Last thing I want is to have a dependency on two benzo’s

Any sage advice anyone ?