11 month old breastfeeds increased

Over the past 6-8 weeks I've slowly reduced my sons boob feeds down to 4 feeds a day (he's 11 months). I always put him on the boob before he has a bath and goes to bed and he normally only feeds for about 5 mins because he's full from dinner so it's more like a drink. Over the last week he's now been feeding for 20-30 mins before his bath which is a huge difference. Did anyone else's bub have a sudden change like this? He's not due to go through another leap for a few weeks but his feeds also haven't changed during any of his other leaps. I'm not concerned, just curious about why the sudden change