Thank you for the photo on the 300ml bottle. However, for hot fill bottle, the bottle design will usually need have panel on the bottle. The purpose of the panel is to absorb the bottle / liquid contraction after cool down from filling temperature of 90 degrees.
Please refer to the bottle design per attach for your reference.
As per my previous email, ASB is using a double blow process for the Hot Fill. It means that in 1 machine, there will be 2 blow station. The 1st blow station will stretch the bottle bigger than the original bottle size by 10-20% with higher temperature. The 2nd blow process within the same machine will blow the bottle to the desired shape and size. The overall hot fill process will classified under 2 stage blow process as the preform will be unload and load to different machine.