Revert "Amend linea_estimateGas reference (#734)"

This reverts commit 772a8e0.

docs/developers/reference/api/linea-estimategas.mdx

@@ -9,13 +9,19 @@ import TabItem from '@theme/TabItem';
 
 # `linea_estimateGas`
 
+:::warning
+
+`linea_estimateGas` is currently unavailable, but we will provide activation dates soon. In the 
+meantime, please get in touch via the [Linea Discord](https://discord.gg/linea) if you intend to 
+use `linea_estimateGas` once it is available.
+
+:::
+
 :::info
 
 `linea_estimateGas` is only fully compatible with endpoints using the Besu client with the 
-[`linea-sequencer`](https://github.com/Consensys/linea-sequencer/tree/main) plugin enabled. See our
-[node running guides](../../guides/run-a-node/index.mdx) to set one up.
-
-If you prefer to use Geth, `linea_estimateGas` is only available 
+[`linea-sequencer`](https://github.com/Consensys/linea-sequencer/tree/main) plugin enabled. If it 
+is unavailable, try updating Besu. If you prefer to use Geth, `linea_estimateGas` is only available 
 if you redirect your request through an Infura endpoint.
 
 We recommend using `linea_estimateGas` rather than alternatives, such as `eth_gasPrice`. 
@@ -27,8 +33,8 @@ being priced incorrectly and failing as a result.
 Generates and returns an estimate of how much gas is necessary to allow the transaction to complete 
 and be published on Ethereum. The transaction will not be added to the blockchain.
 
-[See more information](../../guides/gas/gas-fees.mdx) about estimating gas, and how this API 
-formulates the transaction costs.
+For more information about estimating gas, and how this API formulates the transaction costs, see 
+the [Estimate transaction costs](../../guides/gas/gas-fees.mdx) topic.
 
 The `priorityFeePerGas` returned by this method includes the cost of submitting the transaction to 
 Ethereum, which can vary based on the size of the calldata.