I've lived by Glenmore for 50 years.
The reservoir and the seasonal water levels have been very consistently maintained for longer than that
A caution over the water level that is completely normal?
Not meant to be mean, but all that is going on is you have lots to learn about Glenmore.
The west end IS shallow, always. Two river channels that run on both the north and south side shores are the deeper water you think is there.
Rent a canoe, paddle the lake and go bathymetry on it.
Or just use google earth. This will show you the channels and deep water very clearly.
Wishing you good fishin'.