You seem to have made your mind up already but for what it's worth here's my probably unwanted twopence
Professional head on:-
I wouldn't recommend selling in this market unless you absolutely need to.
I would advise that the tenants remain in the property on the rolling agreement, for you to serve the tenants notice (2 months?) in December and for you to part company with the tenants and the letting agent in February and to start again with a good agent paying between 12 - 15% for full management. The property needs to work for you not for your lettings agent which is what it's doing at the moment.
However, if you have sell in order to buy sooner rather than later then that's what you have to do and the market conditions are irrelevant.