Weekly Mileage

Impossible to say and its not just about mileage anyway.  The 'quality' or intensity of your workouts matter as well.  Consistency and progressive overload (gradually increasing the volume and/or intensity over time) will be your friends.

However, I will say that it looks like you should focus most on the bike & run, since your swim should already allow you to meet your 2:30 goal if the other two get up to that approximate 'level'.

There is a saying in biking "three to maintain, 5 to gain" - meaning three rides/week to maintain your fitness level, and 5 rides/week to improve your fitness lever. With only 50 miles/week you are probably only riding three times/week, unless your rides are fairly short. I cannot comment on the running or swimming, but I believe you need to increase your bike workout frequency, and total miles.

You'd need to provide a bit more data...specifically what makes up your current training volume (how many workouts in each discipline, duration, and pace).  My suspicion, though, is that you'll find it challenging to get to sub-2:30 without doing significantly more running.  To get anything like valid feedback, though, you should log your actual completed workouts.

When I have asked questions in the past, people have always said I should log my workouts on here. So from now on I'm going to log all my workouts. Hopefully in a few months people will be able to offer advice on what I need to do to improve.

For my 1st olympic distance race I was:

Swim 9-12km
Bike 120+km
Run- 25+km