Just got my e-channel sticker in Wan Chai yesterday. My US-issued APEC card didn’t have “HKG” printed, so I didn’t bother to bring it with me. I told the only officer there I had been to Hong Kong via the airport three times. He asked if I had completed three complete trips, and I said it’s my third trip. He said I needed to have completed three trips in and out before I would be qualified. I thought I had read somewhere I could apply on my third trip, but it’s not the case for me.
I then opened and showed him my United digital card. He checked it and quickly approved me.