What's going on with the leaves?

First of all, I'm badly sick so haven't had the time to check on my plants in the corridor. This is also why I only snapped one pic, sorry about that, couldn't stand being outside any longer.

Have had this variegated C. quadriloculare for a while now, been doing really well and I'm really fond of it. Today I noticed this patchiness in the green which wasn't there last time. If I'm not wrong, some leaves had it but some didn't, which is what scared me into thinking this might be pest attack? Also saw some kind of insect flying around but I'm not sure if it's related and couldn't get a good look. If it is, it's not a pest I'm familiar with, so seeking help!

It's in a pot with well-draining mix, and is watered daily or every other day depending on the weather. It's in the corridor, so gets direct morning sun but is shaded for most of the day.

Hoping to get a diagnosis and devise a counterattack while I'm sick so I can come out swinging once I'm well. Thank you!