WooCommerce Subscriptions unexpected value: INF
Short and sweet, because I got no Google results for my search:
When calling WCS_Switch_Cart_Item::get_old_price_per_day()
, I got back INF as a result. After tracking it down, it was because I had filtered wcs_switch_proration_days_in_old_cycle
but had a bug that was resulting in no value being returned.