I am going to go waaaaay out on a limb here (not being professional, I have nothing but pride to loose). Based on the patterning shown in the lower right picture,the center arm positioned up and between the eyes, the lack of webbing, the slenderness of the arms after the mid point, the lack of an enlarged sucker on the first three arms, and the roundness and fullness of the mantle I am going to suggest that she is a Mercatoris and is probably creating eggs. There is a good chance she has mated but either way, if my conclusion is correct, she will be very hungry at this stage. Then she will pick a den (she may try several) and not come out (if she moves, she probably has not yet started releasing the eggs). You are likely to see her start to stack all the small shells in the tank in front of her chosen brooding ground (If you can get your hands on a set of the large purple and white barnacles and place them so you can see the insides, this is ideal). Be sure you provide lots of snail, small conch and/or clam shells (nickel to quarter sized) for her to gather. She will likely use the shells as doors and may pull them into her den as well. Her food demands will start to decline. Trapper ate live initially but once she fertalized her eggs (female octopuses store the sperm after mating and don't fertalize until they release the eggs in their den), would only take freshly killed and blew away anything that might threaten the eggs.
You might review my Journal "Trapper is Finally Here" to see if your octo follows a similar pattern. Please keep posting your/her progress on a single thread so that all of us can follow the adventure and others can use it as a future reference.