If you are the first connection on the CBT outside your house ( designed to serve you and your very near neighbours ) it’s possible that a records/data error is causing the issue (not in the exchange as your were told ) ….
The CBT outside your house goes back to a splitter and then back to the headend , if (for arguments sake ) the splitter node has 4 splitters in the same enclosure , and your CBT should be on splitter 1 but was incorrectly connected to splitter 2 , (this is easily done ) then the symptoms you have would be expected, PON light flashing as stated means ‘light’ is being received but the headend can’t authenticate the ONT , that is because it was expected and entered into data that your address (via the CBT ) was to be on splitter 1 and it’s not it’s on the wrong one , in this example number 2 …the good news , if the Kelly guy advised the ‘Tiger’ team , they should remotely be able to change the data in the headend for your address to splitter 2 ,so your ONT can then be authenticated, otherwise it’s a physical change required in the splitter node putting thus error right ….obviously this isn’t the only possible reason why your PON light is flashing but it’s a pretty common occurrence, once the data is corrected to match the physical setup , any other neighbour orders on your CBT won’t have the same problem as the data is corrected for all addresses on the CBT
