The current Guild Bracket system, ranks Guilds in a bracket, based on their point score. This point score is tied to a bracket since, as an extreme example, 200,000 points in bracket 1 is a lot harder to attain than 200,000 points in bracket 100. For this reason, we decided to err on the side of caution with movement of guilds through brackets, not allowing a guild to jump up (or down) more than 2 brackets in a single week. We may change that in future, to allow more movement, but at the moment we don't have anything to announce.
Your guild's initial placement in the brackets would have taken your guild's level and current placement in the guild-trophy leaderboard when you first registered for guild wars. As a newer guild, that will certainly mean starting some way from the top, but given the 1-3 years most top guilds took to establish themselves, we feel that 6-10 months to rise up the brackets for a new guild is not unreasonable.