The Imperial Premiers are a whole 'nother ball of wax.
That designation was not in use in the era this gun was manufactured. I have pictures of a fabulous Imperial Premier previously owned by a member here. In fact, he sold me his back action Premier (same style as the one in this thread) to finance the purchase of the Imperial. The oak leaf engraving seems to be more 'common' on the Imperial Premiers. Though that is difficult to assess since so few are extant.
In the era of this gun, full coverage oak leaf engraving is much more common on Excellentia guns.
Of course, never say never. I have a 10ga hammer Premier with full coverage scroll engraving. From the time when Scott was putting games scenes on most Premiers.
