Latest twist on the plan for a new Life Time Athletic club at Westfield Montgomery mall: The Rockville location off Montrose and Seven Locks Road had been expected to close once the new one is built — a process that will likely take about two years. But insiders tell us that the existing location has such a loyal membership base that it may end up staying in business after all. Officially, Life Time execs are as tight-lipped now as they were when we first reported on the mall plan back in October. But unofficially, we’re told the existing location is preferable for many of its longtime members and could likely coexist with a larger, fancier club just a few miles away. In fact, we’re hearing that the Rockville club may end up gaining square footage via an expansion to the building next door. But alas, there probably won’t be a rooftop swimming pool like the one planned for the mall. (For more on that, click here.)