I'm sorry to learn you are having an issue with your broadband connection.
Looking at your connection, there is a high peak time traffic fault in your area which is causing slow speeds. The reference number is F005050877 and has a review date of 6th December. As this is a review date it can be subject to change.
As you mentioned you achieve low speeds outside peak hours, can you completed speed tests through a wired connection and let us know the results please?
With the signal drop is this in regards to the wireless connection? If so, you can take a look at this guide to improve the connection > Getting the best WiFi.