And on the guano thing, once you have filed a few ASRs and nothing at all has happened, you tend to lose interest in trying to "fix it".
Takes but a second of your time to mention the issue to the HLO and the RO, or, if you're taking a workparty to a normally unmanned installation, the guys you're carrying. Takes ten minutes to pressure-wash a helideck until it's squeeky-clean.