It is clear there is no one size that fits all when it comes to Large Language Models (LLMs) in the context of service provision and O&M (Operations and Management). The same can be said of the overall LLM strategy. As operators deploy 5G Standalone (SA) with more complex cores, a key question becoming more urgent is whether to build fully customized LLMs incorporating their own data and exploiting domain expertise. The alternative is to harness massive investment made by others such as OpenAI with Chat GPT, Meta with Llama, or Google with its Gemini family. In the latter case, they can still tune the models and bring in their own data, so that approach at first sight would surely…