Filing 485 will make you getting another nonimmigrant visa difficult if not impossible but it doesn't automatically void your previous non-immigrant status. The case is very clear on H/L non-immigrant visa holders, but on the F visa holders it is a little murky. But what you indicated is not right.
You should consult a lawyer. Unless you choose to abandon your F1 by not registering fulltime or using EAD to work or AP for travel, your F1 will NOT be automatically voided.