Aerobic Training Frequency

I’m following the aerobic part of the mountaineering plan in TFTNA to improve my hiking/peak bagging performance and I’m seeing good improvement so far. My weekly aerobic volume target in the first few weeks of my base phase is 6-8 hr. I work regular business hours and can only get out on the weekends. During the week my aerobic training is confined to an incline treadmill. If I go out for a big hike on the weekend, I often end up hitting or exceeding my volume target in that single workout. Is there a benefit to spreading out my training over 3-4 days, rather than 1 big day and 1 treadmill workout on a weeknight?

In case it’s relevant, I lift weights and climb indoors 3-4 weeknights. I come from a powerlifting background and want to retain strength in my core lifts while improving my aerobic fitness and technical climbing skills.