Weaning at 20 months is so doable, especially since you're not pumping at work already, your supply has likely dropped quite a bit during the day, so you're halfway there honestly! What worked for me was doing "don't offer, don't refuse" first to reduce sessions gradually, then slowly replacing the nursing sessions she still wanted with a sippy cup of milk and a cuddle or a small snack instead, the key is giving her something comforting to replace that closeness, not just removing the breast. Some mums I know found that shortening the session little by little each day worked better than going cold turkey, though I'll be honest, a few found their toddlers got really clingy and upset for a week or two no matter what approach they tried, so just brace yourself for some tough nights. If she's very attached and the emotions feel overwhelming on both sides, there are actually lactation consultants here in Singapore who run weaning support sessions, which a few mums in my circle found genuinely helpful rather than just figuring it out alone. You're doing great already, the fact that you nursed this long while working full time is no small thing!